Combination evaporator-condenser assembly with concentric tubular construction



Nov. 8, 1960 Filed Nov. 28. 1958 J. O. EWING COMBINATION EVAPORATOR-CONDENSER ASSEMBLY WITH CONCENTRIC TUBULAR CONSTRUCTION 4 Sheets-Sheet 1 Fig. l2

I l8/ m L 40 James 0. Ewing INVENTOR.

MM 153M1 Nov. 8, 1960 J o, wm 2,959,027

COMBINATION EVAPORATOR-CONDENSER ASSEMBLY WITH CONCENTRIC TUBULAR CONSTRUCTION Filed NOV. 28, 1958 4 Sheets-Sheet 2 Fig. 2

f Carmressar Out/e g 8 Z; Comoressor Outlet 7 4 46 30 9 4 James 0. Ewing 00 d INVENTOR.

n enser vaparafar Compressor ln/ef Nov. 8, 1960 J. O. EWING 2,959,027

COMBINATION EVAPORATOR-CONDENSER ASSEMBLY WITH CONCENTRIC TUBULAR CONSTRUCTION Filed Nov. 28, 1958 4 Sheets-Sheet 3 Fig. 3

James 0- Ewing 1N VEN TOR.

Y Mao/5h.

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J. O. EWING COMBINATION EVAPORATOR-CONDENSER ASSEMBLY Nov. 8, 1960 4 Sheets-Sheet 4 Filed Nov. 28, 1958 rwm . James 0. Ewing INVENTOR.

I MMFML COMBINATION EVAPORATOR-CONDENSER AS- SEMBLY WITH CONCENTRIC TUBULAR CON- STRUCTION The present invention generally relates to a combined evaporator and condenser assembly connected with a compressor in which the assembly is reversible in that the two ,heat exchange mechanisms may be either a condenser or an evaporator depending upon the direction of flow of refrigerant in the system. Specifically, the present invention represents novel and improved structural arrangements having generally the same purposes as that construction shown in my copending application Serial No. 569,527v filed March 5, 1956 now Patent No. 2,910,- 838 granted November 3, 19 59. I I

While the broad concept of a reversible refrigeration cycle has been disclosed in the copending application mentioned above, the present invention has for its primary object the provision of a combination evaporatorcondenser assembly which includes concentric tubes for flow of the refrigerant in either direction in the inner tube and in'either direction in the annular space disposed between the inner tube and the outer tube with substantially the entire assembly being disposed in 'a spiral arrangement with all of the loops lying in the same plane so that the assembly may be immersed in a heat exchange agent and requiring a minimum of space requirement. This feature is extremely desirable in solution tanks employed in various photographic processes in which it is desirable to maintain the temperature of the liquids substantially at a constant level thereby enabling the present invention to take away heat or add heat depending upon the requirements for maintaining the solution substantially at a constant predetermined temperature.

Another feature of the present invention is to provide an assembly in accordance with the preceding object in which a major portion of the concentric tubes are constructed of flexible material so that the orientation of the assembly may bev easily changed.

.A further important feature of the present invention is to provide a reversible evaporator-condenser assembly in accordance with the preceding object in which there is a novel structural arrangement for providing flow restriction for expansion of refrigerant in one direction which restriction is in the form of a capillary tube disposed in the space between the inner and outer tubes'and with the restriction in the other direction of flow being formed by the size of the inner tubular member.

Other features of the present invention will reside in the simplicity of construction, ease of control, adaptation for control by automatic control devices, efliciency in operation, compactness, utility in many places, dependability and generally inexpensive to manufacture.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts vthroughout, and in which:

Figure l is a side elevation of the assembly of the present invention illustrating the orientation of the component parts;

tion of the concentric tubular members and the capillarytube;

Figure 4 is a etailed sectional view of the capillary tube portion of the assembly, on an enlarged scale, illustrating the specific structural details of the capillary tube and the structure of the inner tube;

Figure 5 is a transverse, sectional view taken substantially upon a plane passing along section line 5-5 of Figure 4 illustrating the orientation of one end of the capillary tube in relation to the inner tubular member;

Figure 6 is a detailed sectional view of the attachment between the outer tubular member and the outer hose; 4

Figure 7 is a detailed sectional view of the T-connection employed in the system;

v Figure 8 is a schematic view of the reversing valve in one orientation with the valve set in one position;

Figure 9 is a schematic view illustrating the valve set in another position; and

' Figure 10 is a generally schematic view of a slightly modified form of the invention in which two of the combined condenser and evaporator assemblies of the present invention are employed in the same refrigeration system.-

Referring now specifically to the drawings, the numeral 10 generally designates the combined evaporator and condenser assembly which is incorporated in a reversible refrigeration system. The refrigeration system includes the usual and conventional compressor and motor assembly designated generally by the numeral 12 which may be of any commercially available type' and which may have any desired horsepower. The compressor assembly 12 may be hermetically sealed and may be supported on any suitable base 14 which may have any configuration and which may be supported in any area desired and provided with any shock absorbing equipment that may be deemed advisable. The details of the compressor 12 and the base 14 are not important to the invention in their detail but only in their orientation to the rest of the refrigeration system.

, A looped tube type of condenser-evaporator assembly is generally designated by the numeral 16 and is mounted on the base 14 and includes the usual looped tubes 18 and heat transfer fins 20 thereon. Disposed between the compressor 12 and the assembly 16 is a fan 22 driven by a motor 24 mounted on a bracket 26. The compressor 12 is provided with a pressure relief valve 28 in the discharge line 30 which pressure relief valve is manually adjustable and communicated with a bypass line 32 connected to the intake line 34 of the compressor 12. A reversing valve 36 is provided with the discharge line 30 being connected to one side of the valve and the intake line 34 being connected to the valve at opposite sides in relation to the discharge line 30. A line 38 extends from the top of the assembly 16 to the valve 36 and a line 40 extends from the valve 36 to a T-coupling 42 which forms a portion of the assembly 10. A line 44 extends from the bottom of the assembly 16 and enters into the T-coupling 42 in a manner described hereinafter.

Referring particularly to Figures 8 and 9, when the valve 36 is in the usual position for operation of the refrigeration system in the usual manner, the discharge of compressed refrigerant gases will pass through the line 30 and through passageway 46 in the valve 36 and into the line 38 and thus to the condenser assembly 16 which is acting as a condenser. The inlet 34 is then com,- municated with a passage 48 in the valve 36 which also communicates with the line 40 from the combined condenser and evaporator assembly which is acting as an evaporator. The orientation of the valve 36 is the same in Figure 2 as it is in Figure 8. Each of the passageways 46 and 48 are substantially right angular and in Figure 9, the valve 36 has been rotated 90 so that the compressor outlet is now communicated with line 40- and the compressor inlet is communicated with line 38 wherein the assembly 16 then becomes the evaporator and the assembly 10 becomes the condenser.

Reference is made to Figure 7 which illustrates the details of the T-coupling 42. There is provided an upwardly extending externally threaded integral adapter 50 which receives a coupling nut 52 holding the flared end 54 of the tubular line 40. thereto in sealed relation. The branch of the T-coupling 42 facing the tubular line 44 is provided with an externally threaded adapter 56 similar tothe adapter 50 for receiving a cap 58 similar to, the nut 52 which holds the flared end 60 of the tubular line 14. to the T-coupling 42 in sealed relation. Extending longitudinally from the other branch of the T-coupling 42 is a cylindrical or tubular member 62 secured thereto as by brazing, silver soldering or the like 54. Also secured to the same end of the T-coupling 42 is an inner cylindrical member 66 having an outwardly flared inner end 68 secured to the T-coupling 42 in the same manner. The tubular members or cylindrical members 62 and 66 define a cylindrical space therebetween for receiving a hose 70. or outer tube which is crimped and secured therein by two peripheral beads or grooves 72 formed in the outer cylindrical member 62. The inner cylindrical member 66 prevents collapse of the hose 70 thereby assuring a sealing relationship between the hose 70 and the cylindrical member 62.

Extending longitudinally and concentrically through the hose 70, the inner tubular member 66, the T-coupling 42 and the tubular line 44 is an elongated flexible tube 74 constructed of plastic material such as nylon or the like. One end of the flexible tube 74 is connected to the line 44 by virtue of there being a short cylindrical sleeve 76 disposed into the end of the tube 74. The sleeve 76 is of rigid material and is locked into position and seals the flexible tube 76 to the rigid line 44 by virtue of a peripheral groove or indentation 78 being formed in the line 44 for sealing the sleeve 76, the flexible tube 74 and the rigid tube 44. The sleeve 76 also forms a flow restriction for refrigerant since the internal diameter thereof is less than the internal diameter of the flexible tube 74. A protective and reinforcing sleeve 80 is disposed on the exterior surface of the line 44 to prevent bending of the line 44 at the point of weakening of the line 44 caused by the peripheral crimp or groove 78. With this construction, it will be seen that the lines 40 and 44 are sealed in relation to the flexible tube 74 and the hose 70 respectively with there being a space between the hose 70 and the flexible tube 74 both of which are circular in cross-section and which extend longitudinally in concentric relation to each other.

The hose may be as long as is desired but at the outer end thereof, the hose 70 is connected to a rigid tubular member 82 which will be hereafter called the outer tu bular member or tube. The tube 74 extends longitudinally into the outer tubular member 82 and will hereafter he called the inner tubular member or tube. The outer tubular member 82 is provided with a peripherally extending indentation 84 forming an internal shoulder for receiving the outwardly flared end 86 of a cylindrical member 88 disposed concentrically within the free end of the outer tubular member 82 for receiving the hose 70 therebetween. The outer end of the outer tubular member 82 is provided with a pair of longitudinally spaced peripheral indentations 90 for rigidly securing and sealing the hose 70 to the outer tubular member 82 without collapse of the hose 70. This assembly is somewhat similar to the manner in which the hose 70 is attached to the T-coupling 42. The shoulder defined by the peripheral inwardly extending rib 84 limits the insertion of the flared end 86 of the cylindrical member 88 so that the same may be dropped therein and then brazed or silver soldered into position. The cylindrical member 88 has a diameter greater than the external diameter of the inner tubular member 74 thus providing an annular space between the cylindrical member 86 and the inner tubular member 74 for permitting passage of refrigerant between the outer tubular mem-' ber 82 andthe inner tubular member 74 as well as Within the inner tubular member 74.

As shown clearly in Figure 3 of the drawings, the outer tubular member 82 is formed into a plurality of spiral convolutions with the convolutions lying in the same plane and with the terminal end of the outer tubular member 82 being closed as indicated by the numeral 92. The inner tubular member 74 is concentric with the outer tubular member 82 but terminates in spaced relation to the closed end 92 with the end of the inner tubular member 74 being open as indicated by the numeral 94 and as illustrated in Figure 4.

In substantially the last half of the innermost convolution of the outer tubular member 82, the inner tubular member 74 is connected to an arcuately curved rigid inner tubular section 96 by virtue of a rigid sleeve 98 disposed in the end of the inner tubular member 74 together with an inwardly extending peripheral projection 100 in the portion of the rigid inner tubular section 96 which telescopes over the inner tubular member 74 thereby sealing the flexible inner tubular member 74 to the rigid inner tubular section 96 which forms a continuation thereof. The sleeve 98 also forms a flow restriction in the inner tubular member 74.

Adjacent to but spaced inwardly from the outer end of the rigid inner tubular section 96 is a peripherally extending inwardly extending shoulder 102 which forms.

a valve seat for a freely movable ball valve 104. In the free end of the rigid inner tubular section 96, there is provided a cylindrical sleeve 106 disposed Within the inner end of the outermost section 108 of the flexible inner tubular member 74 with the portion of the rigid tubular section 96 telescoping over the outermost section 103 being peripherally and inwardly crimped as indicated by the numeral 110 for sealing the outermost section 108 of the inner tubular member 74 to the rigid inner tubular section 96.

Disposed in coiled relation about substantially all of the outermost section 108 as well as a portion of the rigid section 96 is a coiled capillary tube 112 having a free and open end 114 adjacent to but spaced from the an open end 118 in facing relation to the ball valve 104 whereby the ball valve 104 may roll against the open end 118 so that the open end 118 forms a stop for the ball 104 whereby the ball 104 can only move between the open end 118 and the valve seat defined by the peripheral shoulder 102.

The orientation in Figure 10 isv generally equivalent to that shown in Figures 1-9 with the exception that two concentric tubular assemblies generally designated by the numeral 10' are employed with one ofthem being hooked to line 38" by a T-coupling 43 similar to T-coupling 42, with the inner tubular members being interconnectedby a pipe 44' having the sealing ring 78' therein.

In operation, assuming that the refrigeration system operates in the usual manner and the valve 36 is set in the manner as shown in Figure 8, the compressor 12 assent will operate upon demand such as by useof a thermostat or other heat responsive device whereupon refrigerant refrigerant will then enter the ppm: end 1 1 8 of i the capillary tube 112 and will proceed through the capillary tube 112 and be discharged from the free end 114 thereof at which time therefrigerant expands into the larger area between the outer tubular member 82 and the inner tubular member 74 thus causing the rigid outer tubular member 82 to become cold and absorb heat. The expanding or boiling refrigerant caused by the absorption of the heat will then proceed back through the T-coupling 42 and out through the line 40, the valve 36 and into the intake 34 of the compressor 12 thus completing the cycle. The capillary tube 112 forms the fiow restricter and expansion valve such that the refrigerant may expand in the usual manner in the outer tubular member 82.

When the reversing valve 36 is shifted to the other position and assembly 10 acts as a condenser and assembly 16 as an evaporator, the refrigerant goes from the compress-or 12 into the compressor outlet line 30 and through the valve 36 into the line 40. From the line 40 it proceeds between the outer tubular member 82 and the inner tubular member 74 and will proceed completely to the end of the outer tubular member 82 where it is cooled and then will proceed into the open end 94 of the inner tubular member 74. The pressure and movement of the partially condensed refrigerant will move the ball valve 194 away from the seat 102 in a pulsating manner thus permitting passage of the refrigerant through the restrictions which maintain a pressure differential including the sleeve 106 and the sleeve 98 and thence into the inner tubular member 74. As the refrigerant passes through the inner tubular member 74, it will pass back through the T-coupling 42 and through the flow restricter sleeve 76 wherein the refrigerant which has been cooled during its passage through the assembly 10, now acting as a condenser, will expand into the assembly 16 thus cooling the assembly 16 and absorbing heat from the fins 20 and the tubes 18. The boiling and evaporated refrigerant will then proceed back through the valve 38 to the compressor inlet line 34 for repeat of the cycle. In this cycle of the operation, the valve 104 will normally rest against the seat 118 when the refrigerant is in a purely gaseous state. However, when some of the refrigerant is in a liquid state, the liquid refrigerant or combined liquid and gaseous refrigerant will actually cause somewhat of a bubbling action or pulsing action as slugs of liquid refrigerant and gaseous refrigerant pass through inner tubular member 74.

In the device of Figure 10, the device works in the same manner except that another of the assemblies 10 replaces the assembly 16 and the .inner tubular members of the two assemblies are intercommunicated and the device operates in the same manner.

The reversing valve may have a position wherein the pressures in the device may be equalizd for the purpose of assisting in the reversing of the refrigeration system. It takes very little time for the outer tubular member 82 to become extremely cold when it is normally hot such as when it is acting as a condenser since the release of the liquid refrigerant will immediately permit the refrigenant to expand for absorbing heat thus immediately turning the outer tubular member 82 from a hot condenser member to a cool evaporator member. When reversing the cycle in the other manner, it take some operation of the compressor to unload the boiling and residual expanding refrigerant from the assembly 10 inasmuch as the assembly actually acts as a combined receiver and evaporator and it is necessary to remove all" of the liquid refrigerant from the assembly 10 before the as sembly 10 can be heated by the incoming hot gaseous refrigerant from the discharge side of the compressor.

The pressure relief valve 28 may be adjusted so as to control the vaporpressure or boiling point of the refrigerant in the assembly 10 when it is acting as an I evaporator and tocontrol the amount of heatingin as- 10 sembly 10 when it is operating as acondenser' by-remotely controlling the boilingpointofthe'refn'gerant-in assembly 16. This alsoi' will pr'olong the useful life of the compressor and motor therefor since the compressor maybe provided for the compressor and motor assembly and also for the reversing valve aswell as for the pressure relief valve so that the devicemay be adapted for:

use in many orientations and for many purposes.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In a reversible refrigeration system, a heat exchange assembly comprising an outer tubular member and an inner tubular member arranged concentric therewith, said outer tubular member having a closed end, said inner tubular member having an open end spaced from the closed end of the outer tubular member thereby communicating the outer and inner tubular members for flow of refrigerant, a one-way check valve in said inner tubular member for preventing flow of refrigerant from the inner tubular member into the outer tubular member from the outer end of the inner tubular member, capillary tube expansion means having an open end communicating with the interior of the outer tubular member and having another end communicating with the interior of the inner tubular member inwardly of the check valve whereby refrigerant may flow through the capillary tube and be discharged into the outer tubular member for expansion and absorption of heat.

2. The device as defined in claim 1 wherein said check valve is in the form of a gravity operated ball valve resting against a valve seat, said ball valve serving to restrict flow of gaseous refrigerant in the other direction in the inner tubular member, said ball valve adapted to be moved away from the seat by liquid refrigerant thereby providing for flow of liquid refrigerant into the inner tubular member from the outer tubular member when the heat exchange assembly is employed as a condenser.

3. The structure as defined in claim 1 wherein said capillary tube is spirally wound around said inner tubular member in concentric spaced relation thereto.

4. A reversible refrigeration system comprising a compressor, a first heat exchange assembly, a second heat exchange assembly, each assembly including an outer tubular member and an inner tubular member concentric therewith, the inner tubular member of said assemblies being interconnected, and a reversing valve interconnecting the compressor intake and outlet with the respective tubular members for reversing flow of refrigerant, one of said assemblies including a capillary tube means intercommunicating the outer end of the inner tubular member and the outer tubular member and restricting the flow of refrigerant so that the same may expand for absorbing heat, the outer end of the outer tubular member being closed for flow and expansion of the refrigerant from the inner tubular member to the outer tubular member.

5. The combination of claim 4 wherein said outer tubular. member and inner tubular member are wound into a fiat spiral coil.

' 6. The structure as; defined in claim 4 wherein said means.forirestrictingfiow includes a coiled capillary tube disposed. between the inner and outer tubular members and communicating, the interior of the inner tubular member and the interior of the outer tubular member for expansion of the refrigerant into the outer tubular member rm cooling the same.

7. The. structure as defined in claim 6 wherein, the

outer end of said. inner tubular member is provided with a check valve for preventingflow of liquid refrigerant towards the end qt, the inner, tubular member; when the,

assembly isvacting as an evaporator, said inner tubular member having an open end for permitting flow of condensed refrigerant inwardly into the inner tubular member and past theeheek valve when the assembly is acting'as a condenser, said capillary tube extending into the inner tubular member inwardly of the check valve for flow of liquid refrigerant therethrough forexpansiqn; thereof.

8. The structure: as defined in claim 7 wherein said check valve is a gravity-operated balleheck valve freely; rollable in said inner tubular member and normally en.-

gagcd with av valve seat.in the inner tubular member,

the inner end of said capillary tubehaving a terminal end disposed in the path of movement of the ball check UNITED, STATES PATENTS 2,467,078 Cathenzli; Apr. 12, 1949; 2,785,542 Mar. 19, 1957; 2,847,833 7 H V n} Aug. 19, 195 8 2,913,609 Lennard Nov. 17, 1959 

